The Forum for Gauge 3 Model Trains

Rolling Stock => Carriages & NPCS => Topic started by: John Candy on Dec 21 2022 21:41

Title: "Forward" into 2023.
Post by: John Candy on Dec 21 2022 21:41
Great_Central_Railway_Coat_of_Arms.jpg

Alongside the GWR coaches being produced, I am working on some LNER types.

Moving into the New Year, some 60ft Great Central corridor stock is being prepared.
The corridor brake compo is underway and attached is the rendering of the OpenSCAD file for the first of the three sections, which will form the corridor side of the carriage.

The design of the 60ft 1911 stock is very modular and the components already produced can be easily rearranged to produce an all-third, composite and a brake third.

These carriages ran on 10ft 6in wheelbase bogies, the parts for which will be included in the downloadable STL packages which will be made available.

gcr1.jpg
gcr2.jpg gcr3.jpg
Title: "Forward" : Part 1 GCR 1st/3rd Corridor Composite
Post by: John Candy on Jan 11 2023 07:16
"Forward" : Part 1 GCR 1st/3rd Corridor Composite

This is a package of STL files which will produce the sides of a 1st/3rd composite of Great Central 1911 60ft corridor stock (a type which ran well into the BR era). There are six components to each side (12 files in all) which print the corridor and compartment sides of the coach. The sides have been designed in sections to fit a 350mm print bed.

http://gauge3.info/downloads/GCR/GCcompo(1).zip

The sides fit between  the ends to produce the scale 60ft length.
The photos show a sample section which is loosely assembled and roughly brushed with primer for purposes of showing the detail.

To enable the upper section of the body to be thinner than the tumblehome/matchboarded lower section (to keep the glazing inset realistic), the upper and lower sections are printed separately. The upper section is located by a rebate in the lower (matchboarded) section.

The ends and 10ft 6in GCR bogie patterns are in preparation, along with seating and corridor partitions.
The ends of these coaches appeared in both panelled and matchboarded types and the files for both types of end are in preparation (these coaches were produced over several years and photos suggest the ends of later-built examples were matchboarded, possibly an economy introduced during the Great War).

The intention is to produce matching stock of the following types:
All First,  All Third, Brake Composite and, possibly, a 5 -compartment Brake 3rd (but the dimensions for the van section window and door spacings are currently proving elusive).

gcrw1.jpg gcrw2.jpg
Title: Re: "Forward" into 2023.
Post by: IanT on Jan 11 2023 22:33
"The sides have been designed in sections to fit a 350mm print bed"

I thought that this would rule out my Sovol John, as it's bed is only (physically) 300mm x 250mm. I download the STLs (for a quick peek) and the first one seems to show up as 191 x 56 x 5mm when opened in Cura, so should be OK for my printer. Is there a longer one in the set?

Regards,

IanT
Title: Re: "Forward" into 2023.
Post by: John Candy on Jan 12 2023 04:13
Ian,

The section you quote is, unfortunately, one of the shorter parts....the largest sections of the 1st/3rd compo are 338 mm in length.
The sides are divided so that the joints coincide with the hinge edges of doors. The minimum distances between the hinged door edges are 82.125mm for 3rd class compartments and 98.57mm for 1st class, so it was a juggling act to make it fit onto a 350 bed.

The window/door spacings on the other types are different (principally the result of the length of lavatory compartments varying considerably .... presumably to ensure consistent 1st and 3rd compartment widths within the 60ft overall length) and the longest sections of the All Third and All First are under 300mm (longest being 295.72).

I am still working on the Brake Compo but it looks as though all sections will be <300 (longest so far is 254).

The Brake 3rd will likely break down into modules <300.

Hopefully, you will be able to make use of at least some of these designs.

A possible alternative  with the 1st/3rd compo would be to reduce the lengths of the end modules by separating the lavatory section from the compartments at the closest door edge (would need to be done by tinkering with the OpenSCAD file).

Regards,
John.
Title: Re: "Forward" into 2023.
Post by: Nick on Jan 12 2023 08:55
John,

Gosh, much more of this and I'll be tempted into buying a 3D printer. Seriously, I can only applaud both what you are doing and the spirit in which you are doing it. Keep it up.

Nick
Title: Re: "Forward" into 2023.
Post by: IanT on Jan 12 2023 09:43
Ok Thanks John.

" (would need to be done by tinkering with the OpenSCAD file) "

And I had a feeling you might suggest that...  :-(

Regards,

IanT
Title: Re: "Forward" into 2023.
Post by: John Candy on Jan 12 2023 11:22

QuoteAnd I had a feeling you might suggest that...  :-(
Ian,
I wasn't expecting you to edit the files...... with all the cutouts/recesses, bolections, etc. the files are long and convoluted.
Knowing my way around the files, it is not a big job.
What are the max side-to-side and front-to back dimensions you have available for printing...I presume slightly less than the overall bed size?
Regards,
John

Title: Re: "Forward" into 2023.
Post by: IanT on Jan 12 2023 14:57
Well (obviously!) it's not mentioned in the Sovol Owner Manual John but external reviews suggest a Build Volume of 280mm (X) x 240mm (Y) x 300mm (Z). It's the 'X' that's of interest of course but if you can get that a bit under the 280mm Max that would be excellent.

Not a high priority for me at the moment, as I'm busy with the L&Y BEL project (so don't break your neck) but I'd certainly like to try a carriage print. I've been generally pleased with the quality I can acheive - not perfect but pretty good.

Regards,

IanT
Title: Re: "Forward" into 2023.
Post by: cabbage on Jan 13 2023 10:49
As the most highly qualified computer geek in the G3S... I have had a look at the source code for the parts above. The source is a vast improvement on what I have seen before but it is still heavily stylised but the style is consistent. The main problem is that the code is built as a monolithic "write once" approach. This is fine for writing small pieces of code, but when it comes to writing the code to print locomotives and rolling stock -well...

That is not to say they do not produce an excellent print(!)

RepRaps and OpenScad have allowed us as a society to take a quantum leap in what we can do and I look forward to other prints.

At the moment the code produced similar to the early works of HG and LBSC.

Regards

Ralph
Title: Re: "Forward" into 2023.
Post by: IanT on Jan 13 2023 12:14
Well Ralph

I'm certainly not qualified to comment on anyone's code but I will be grateful if John is able to help me fit these prints onto my Sovol. The ability to use others people hard work in this way is a great gift and one that I very much appreciate. So I'm not going to worry too much about the programming 'asthetics' if the end result prints OK.

For various reasons, I choose to walk a different 3D-CAD path (e.g. not Open SCAD). I'm pretty sure a 'Professional' Draftsman would have fits if he watched me drawing with SE (lot's of backtracking and corrections!) but as long as I get there in the end, that has to do.  :-)

Regards,


IanT
Title: Re: "Forward" into 2023.
Post by: cabbage on Jan 13 2023 12:58
IanT,
I come from a 80x25 line green screen terminal background. This meant that EVERYONE in the company had to write in the same style and only specific data names were allowed.

There several systems of programming around JSP/KSD being the most famous. If you wrote programs for HMGOV you had to use precise SSADM(3) and Data Entity Life drawing - or get sacked!

The system I use normally is the commercial one called GRAPES.

I did post the construction, design and coding on another forum of a class22.

I still think they are in a state of shock....

Regards

Ralph
Title: Re: "Forward" into 2023.
Post by: John Candy on Jan 13 2023 23:29
In my defence, I will argue there are times when unorthodox thinking comes in useful!

Back in the early 80's, I dragged the City law firm I was with into the 20th Century and wrote a suite of programs to handle specific tasks for which commercial programs were not readily available.

One involved trust accounting, where an instant overview of all holdings (i.e. shares and bank funds) needed to be available and attributable to individual trustee/clients.

A short while after I had implemented the system, a professional systems programmer (whose wife happened to be a Barrister) asked the senior Partner whether he could be introduced to me. I already knew (via a "mole" in the firm he had been advising) that he had been struggling for a couple of years attempting to design a system similar to mine (I had, incidentally, written my suite of programs over the four days of the 1983 Easter weekend).

He couldn't get his head around how you could integrate the necessary components while complying with the Solicitors' Accounts Rules.

I had to explain the method of the coding to him several times before the "penny dropped". He took a lot of convincing that the system was compliant with the rules because of the unorthodox fashion (in his view) of the way the data was pooled in a single database.

Via the  "mole" , I learned that, immediately after the meeting with me, he had telephoned his client firm and claimed to have had a "flash of inspiration" and had solved the problem!

I rest my defence!

Regards,
John.
Title: Re: "Forward" into 2023.
Post by: John Candy on Jan 14 2023 07:51
Ian,
A new fiile containing reduced-length components is at

https://gauge3.info/downloads/GCR/GCcompo(1compact).zip

The longest item is now 272mm.

The compartment side of the coach is now in four lengths (eight components) and the corridor side in five lengths (ten components).

The original set of files (for which a 350mm bed is required) remains in situ.

Regards,
John.
Title: Re: "Forward" into 2023.
Post by: IanT on Jan 14 2023 10:06
Well, I don't really care how either of you are doing all this, as long as you continue to share it!  :-)

John, thanks very much - that was quick!  I will have a go at these once I've got the L&Y BEL out the way.

Regards,

IanT
Title: Re: "Forward" ... GCR All Third Corridor
Post by: John Candy on Jan 17 2023 10:44
GCR All Third Corridor (1911 stock)

This is the All Third (which is of matching type/style to the 1st/3rd composite coach).

https://gauge3.info/downloads/GCR/GCRthird(1).zip

The coach is symmetrical about the centre line on both sides, so, while there are six files for the upper sides (3 each for compartment side and corridor side), there are just three for the lower sides (you require two printed copies of each of the lower side files).

This version fits a 350mm printer bed (there will be a "compact" version for smaller printers).

The All First will follow next, followed by the files for the ends and then the matching Brake coaches.
Title: Re: "Forward" into 2023.
Post by: cabbage on Jan 17 2023 14:02
John,
My tronxy has a print bed of 330x33m. Most domestic printers have a bed of 180x180mm. Although 220x220mm becoming common.

Regards

Ralph
Title: Re: "Forward" ... GCR All First Corridor (1911 stock)
Post by: John Candy on Jan 19 2023 21:20
GCR All First Corridor (1911 stock)

This is the All First Corridor (1911 stock)
http://gauge3.info/downloads/GCR/GCRFirst(1).zip (https://gauge3.info/downloads/GCR/GCRFirst(1).zip)

As with the All Third, the coach is symmetrical about the centre line on both sides, so, while there are six files for the upper sides (3 each for compartment side and corridor side), there are just three for the lower sides (you require two printed copies of each of lower side files).

The longest component is  295mm in length (there will eventually be a "compact" version for smaller printers).

The Brake 1st/3rd Composite is in preparation together with coach ends of the matchboarded type.
Title: Re: "Forward" GCR 1911 Stock matchboarded ends
Post by: John Candy on Jan 24 2023 21:21
GCR 1911 Stock .... matchboarded ends.

As mentioned in a previous post, two types of end appear in photos of this stock. Some have panelled ends, while others have matchboarded ends.

I have uploaded to  https://gauge3.info/downloads/GCR/GCR_ends(1).zip 

which contains files for the matchboarded inner ends and brake ends (the panelled type will follow).

The files are suitable for use with both gangwayed corridor stock and non-gangwayed (suburban/compartment) stock  The gangway connectors will be provided later as add-ons.

The Brake 1st/3rd composite and Brake 3rd (5-compartment) are almost ready.

I will likely produce a semi-corridor lavatory composite of non-gangwayed stock (a similar arrangement to that later used by Gresley for LNER stock.

brake end.jpg plain end.jpg
Title: "Forward" : GCR 1911 Stock Panelled Ends and Gangway Connectors
Post by: John Candy on Jan 25 2023 18:16
GCR 1911 Stock Panelled Ends and Gangway Connectors

This is where it can become confusing, so (if you are intending to build these carriages) I suggest you keep this note to hand.

My previous post contained the link to the matchboard ends which are basically the same for gangwayed (corridor) and non-gangwayed (local/suburban compartment stock). The only difference being the need to add the gangway connector base mounts which are at https://gauge3.info/downloads/GCR/BS_gway_conn.stl

The "bellows" section fits into/onto this base. I have not yet decided whether to print the bellows section in flexible "TPU" material, print rigid or to fabricate individually.

Both types of carriage (gangwayed and non-gangwayed) were also built with panelled/beaded ends BUT the arrangement of panels differed between the two, so don't add connectors to the non-gangwayed pattern.

To produce a gangwayed carriage you require https://gauge3.info/downloads/GCR/GCR_ends(2).zip (the connectors are included as part of the ends).

To produce a non-gangwayed carriage you require httpS://gauge3.info/downloads/GCR/GCR_ends(3).zip


BS gangway connector.jpg brake end gangwayed.jpg plain gangwayed end.jpg brake end nogway.jpg plain end nogway.jpg
Title: Re: "Forward"....GCR 10ft-6in Bogie
Post by: John Candy on Jan 31 2023 06:36
GCR 10ft-6in Bogie

I have been working on the side frame for the 10ft 6ins wheelbase bogie used under the majority of the coaches of the type being modelled (as well as the "Barnums").

It is massive for a 4-wheel bogie and the suspension arrangement is very complex (see  https://gcr-rollingstocktrust.co.uk/2022/11/29/rst-historic-achievement-major-bogie-rebuild-completed/ 
for the examples on the preserved "Barnums").

I am still working on the additional springing and damping details which will be a separate unit to fit behind and beneath the main unit.
Meanwhile, the main sideframe component is at

https://gauge3.info/downloads/GCR/bogie(1).stl

The axlebox cover is the later GCR type which replaced the angular type with which they were originally built.

GCR bogie 1.png

The Brake Composite and Brake Third (5-compartment) are now complete ... I just have to write the notes before uploading.
Title: Re: "Forward"....GCR 10ft-6in Bogie (spring detailing unit)
Post by: John Candy on Feb 01 2023 05:14
The springing arrangement of the GCR Spencer Moulton bogie is complex and very few photos provide any view of the detail and then only snippets. The only arrangement drawing I found was very difficult to read/interpret ....it provides the mechanical detail but gives few clues as to external appearance. I suspect the restored bogies are not visually identical with the originals, judging by photos I have seen.

Attached is my best effort at producing a single unit which attaches to the inside of the main sideframe.

The first two images shows the detailing unit as provided by the file

https://gauge3.info/downloads/GCR/bogie(2).stl

The others images show how it is attached to the main sideframe unit.


gcb5.png gcb6.png gcb1.png gcb4.png gcb3.png